Why Digital Pressure Gauges are the Best

Pressure gauges and switches are some of the important instruments used in a plant to monitor equipment and process flow. A set of digital pressure gauges will indicate whether a pump is working properly by showing the pressure differential between the suction nozzle and the discharge. The differential should match the psi for which the pump was designed for better efficiency. If the discharge pressure is not right, either the system or the pump must be adjusted to run optimally. This will reduce the occurrence of problems like cavitations and helps the pump’s bearings and mechanical seals to last for years.

Different types of pressure gauges

-        Gauge pressure gauge – measures all pressure relative to atmospheric pressure which changes with the weather; however, it only measures positive pressure.

-        Compound pressure gauge – uses atmospheric pressure as its reference point. It measures both vacuum and positive pressures.

-        Vacuum pressure gauge – also uses atmospheric pressure as its reference point but it only measures vacuum pressures.

-        Sealed pressure gauge – its reference chamber is sealed in the plant to protect internal electronics and components and used primarily for dusty, dirty and wet environments. These gauges measure only positive pressures.

-        Absolute pressure gauges – the reference chamber is also sealed but under full vacuum. These gauges measure both vacuum pressure and positive pressure.

Why the digital pressure gauges make a sound investment

Digital pressure gauges are more accurate and stable. The gauge readings are not affected by vibration and it doesn’t require frequent calibration. The features of the digital pressure gauges such as multiple units of measure help the users with conversion. In order to make digital pressure gauges more affordable for the end user, they can plumb in a valve at the suction nozzle and discharge of their pumps. This will allow them to use one set of gauges on multiple pumps which reduces their expenditures but at the same time enjoy the advantages of digital pressure gauges.

Absolute pressure gauges  

Using the absolute pressure gauge on pumps is a good idea particularly when the end user requires a sealed chamber for protection against dust and moisture in the environment. However, because it is not vented into the atmosphere, the readings change according to atmospheric pressure changes. Operators need to be properly trained in reading the absolute pressure gauges. For example, what is zero on a compound gauge is actually the natural pressure of the atmosphere at the application’s elevation while on the absolute pressure gauge; it would read somewhere close to 15 psi instead of zero.

Analog pressure gauges

Analog pressure gauges are less accurate and less reliable. The needle and internal gears are affected by vibration and if left on a vibrating line for too long, the gauge will quickly wear which will require either recalibration or replacement. Reading the needle of an analog pressure gauge can contribute to its inaccuracy since if it has an error band of 5% or less, it can be magnified by visual error. The user who will be reading the gauge will be guessing in decimals and the angle from which the gauge is read increases the error.